1. Field of the Invention
The present invention relates generally to methods and apparatus for unclogging drain pipes. More particularly, it concerns an anti-clog water jet nozzle designed specifically for a plumbing cable having an internal fluiding-conveying passageway.
2. The Backqround Art
Drain cleaning apparatus are known in the plumbing industry for dislodging and flushing clogs in drain pipes. The conventional prior art drain cleaning methods used to involve a two step process. In step 1, the operator feeds a plumbing cable, often referred to as a snake, through a drain pipe in order to push out, dislodge and otherwise unclog debris within the drain pipe. In step 2, the operator feeds a jet spray hose into the drain pipe, often utilizing a reverse spray nozzle which produces an annular backward spray of water. The water spray operates to dislodge and flush out clogs and other debris from the drain pipe.
Attempts have been made to improve the state of the drain cleaning art. For example, it is known to combine the plumbing cable and jet spray hose into a single cable member containing an internal co-axial hose which discharges a water spray from a nozzle affixed to the end of the cable. These cable hose combinations enable an operator to perform the two steps mentioned above in a single, easy step. Such cable hose combinations are disclosed in U.S. Pat. Nos. 4,773,113 (issued on Sep. 27, 1988 to Russell), 4,420,852 (issued on Dec. 20, 1983 to Bowlsby) and 4,312,679 (issued on Jan. 26, 1982 to Klein, Sr.).
However, the cable hose combinations which have been developed are characterized by a number of disadvantages and have therefore not come into general use. For example, one method of use is to insert the cable hose into a clogged pipe until its nozzled end is just upstream of the clog, then discharge a water spray to flush the clog on down the pipe. If the clog is not immediately broken up or dislodged, the result is that filthy water will back up quickly in the pipe and flood out through the inlet. Another method is to penetrate the clogging debris with the nozzled cable until the nozzle is just downstream from the clog, then discharge a backward water spray from the nozzle to slowly break apart the clog from its downstream end to thereby avoid backing-up and flooding. However, the nozzle holes are prone to become clogged when the nozzle penetrates the debris, requiring the operator to retrack the cable and clean out the nozzle, often three or more times before the nozzle can be placed downstream from the debris without becoming prohibitively clogged.